Thermostatic valve



Nov. 5, 1963 E. J. KIMM 3,109,589

THERMOSTATIC VALVE V Original Filed Oct. 8, 1959 t IN V EN TOR By Ecumld T- United States Patent Ofiflce 3,109,539 Patented Nov. 5, 1963 3,109,589 THERMOSTATIC VALVE Ewald J. Kimm, Dayton, Ohio, assignor to United Airgaft Products, Inc, Dayton, Ohio, a corporation of hit) Original application (let. 8, 1959, Ser. No. 845,266, now Patent No. 3,037,747, dated June 5, 1962. Divided and this application Oct. 4, 1961, Ser. No. 142,986

2 @laims. (Cl. 23699) This invention relates to valves useful in valve and heat exchanger assemblies having especial reference to small and light weight integrated devices of the kind described for use in aerial craft. This is a division of application Serial Number 845,266 filed October 8, 1959 by Robert E. Preston and Ewald I. Kimm for Heat Transfer Apparatus now Patent No. 3,037,747.

An object of the invention is to adapt assemblies as described to the use of high pressure, high temperature air as a source of heat to warm fuel and for like purposes.

Another object of the invention is to construct a valve providing for accurate control over a flowing, high pressure, high temperature air through thermally responsive means in which fluid pressure eflfects upon the valve are substantially balanced out.

Another object of the invention is to provide a generally new valve unit in an assembly as described, characterized by a valve resiliently mounted to take up positions as indicated by a thermostat without being directly connected to such thermostat.

Other objects and structural details of the invention will appear from the following description when read in connection with the accompanying drawing, which is a view in side elevation partly broken away, of a valve and heat exchanger assembly in accordance with the illustrated embodiment of the invention.

Referring to the drawing, in its illustrated embodiment the invention is comprised in a fuel heater, flowing liquid fuel which may entrain ice crystals being warmed by high temperature air drawn from a suitable source. The assembly is a fabricated structure, being made up of a number of parts and sub-assemblies of parts joined to one another in a brazing or like operation. The assembly comprises a heat exchanger casing 10, a valve casing 11 in parallel adjacent relation to the heat exchanger casing and an interconnecting manifold 12.

Installed on one end of the heat exchanger casing is a flange 12-a receiving a mounting ring 13. The latter provides a seat at its inner end for a perforate header plate 14. The opposite end of the casing 10 is closed by a domelike cap 15. In inwardly spaced relation to the cap 15 is a similarly formed part 16 secured to a flange 17 mounted to the exterior of a second header plate 18. Tubes 19 extend between and interconnect the header plates 14 and 18, the tubes being made thin for heat transfer through their walls at a favorable rate. Stiifeners 21 are mounted upon the tubes and lend strength to the tube assembly, it being understood that within the heat exchanger cas'ing and extending between the plates 14 and 18 is a substantial number of closely spaced heat exchange tubes, the two here shown being merely representative of the total number.

The heat exchanger casing 10, with its contained core of heat exchange tubes, accordingly provides a place for an interchange of heat between separated fluids, one flowing through the tubes and the other flowing around and between tubes. The described other fluid enters the casing by way of an upper inlet 22, is permitted to descend transversely across the tube bundle or core and leaves the heat exchanger casing by way of an oppositely disposed opening 23. The described one fluid is in the illustrated instance directed through the assembly of tubes in a dual pass. The mounting ring 13 is bisected in its interior by a rib 24. A partition 25 extends from the rib 24 to the header plate 14 and so effectively separates the mounting ring interior into upper and lower passes each communicating with a respective group of tubes. At the opposite end of the casing the part 16 and the plate 18 define a turn around chamber 26 in which the fluid passing through the first or upper group of tubes may return in the opposite direction to the second or lower group. The described one fluid accordingly enters and leaves the heat exchanger casing at the same end thereof.

The valve casing 11 has mounted on its opposite ends I flanges Z7 and 28. In an intermediate portion of the valve casing are spaced apart supports 29 and 31 which provide a mounting for a valve sleeve 32. The latter has a vertical solid portion 33 acting as a closure for one end of the casing 11, with the sleeve proper extending axially inwardly 0f the casing and having a portion resting on the supports 29 and 31 which act in effect as support bearings. The sleeve 32 is more particularly made up of a circumferential series of longitudinally extending spaced apart portions 34 interconnecting the solid portion 33 and an annular ring 35, and, beyond these portions, a similarly extending circumferentially spaced apart series of portions 36 interconnecting the annular ring 35 and a similar ring 37. A free flow of fluid axially through the rings 35 and 37 and laterally between the portions 34 and 36 thus is possible. At the inner ends of the rings 35 and 37 are respective valve seats 38 and 39. On opposite sides of the bearing supports 29 and 31 the casing 11 is formed with openings 41 and 42 communicating through the opening 23 with the interior of heat exchanger casing 10. Intermediate the bearing supports 29 and 31 is an outlet opening 43 in the casing 11. Flow from the heat exchanger casing, of the fluid which passes over and around the tubes 19, accordingly is directed to the valve casing by way of the openings 41 and 42 and follows two paths through the ring portions 35 and 37 and of the sleeve 32 to outlet 43.

Controlling this latter flow is a valve unit 44 comprising a tubular portion 45 on which are spaced flange or valve portions 46 and 47 adapted to seat upon or to engage respective valve seats 38 and 39. So positioned, the valve unit 44 closes off fluid flow to the outlet 43. A shaft 48 extends longitudinally through the tubular portion 45 of the valve unit and through the valve thereon and has collars 49 and 51 in sliding engagement with the valve unit. Further, on the exterior of the tubular portion of the valve unit are longitudinally spaced apart sets of guide vanes or flutes 52 and 53 having sliding bearings respectively in the rings 35 and 37. The lefthand or inner end of the shaft 48 has a bracket 54 fixed thereto providing a base for one end of a compression spring 55, the other end of which bears upon the valve 47 of the valve unit urging it rightward or in a direction to engage the valve portions with the seats 38 and 39. Being fixed thereto, the bracket 54 may be considered a part of shaft 48. Engaging the opposite end of the valve unit, through a loosely arouses mounted sleeve 56, is a compression spring 57 based upon the solid portion 33 of the sleeve 32. The shaft 48 extends through and beyond the sleeve 56 and is pinned to an extension 53 thereof having a stem 59 which projects through and beyond end closure 33 in order that the tip thereof may serve as an indicator to the longitudinal position of adjustment of the valve unit. 7

Such longitudinal adjustment of the valve unit is under control of a thermostat 61 of aknown kind wherein a material having the property of forceful expansion under heat is contained in a case 62 and arranged as a result of its expansion relatively to extend a plunger 63 at its outer end. The thermostat 61 is mounted in a wall 64 stationarily mounted in the casing 11' between the opening 41 thereof and that end opposite the end closed by portion 33 of the valve sleeve. The wall 64 defines with the described adjacent end of the casing 11 a chamber 65 opening to the exterior of the casing through the open end of the latter and through a lateral opening 66. The thermostat 61 is in the drawing. Under the pressure resiliently applied through spring 55, therefore, the valve unit is moved to a seated or closed position and at the same time spring 57 is compressed. In response to cooling of the thermostat the spring 57 is allowed to expand and in so doing to move the valve unit 44 leftward or to an open position and at the same time to return the plunger 63 inward within the thermostat. An over travel of the thermostat beyond that necessary to engage the valves .46 and 47 with their respective seats is absorbed by a yielding of the spring 55. The exterior of the thermostat 61 is suitably formed to accommodate seals 67 and 68 which preclude intercommunication between the spaces on opposite sides of the wall 64; Between the seals 67 and 68 is an annular space 69 communicating through a passage 71 in the wall 64 with the exterior of the valve casing whereby to avoid any build up of pressure between the sealing elements 67 and 68 and to carry off any fluids which may gain access to the space 69.

On the lefthand end of the valve and heat exchanger assembly, as viewed in the drawing, there is bolted or otherwise secured a plate 72. providing a mounting for a housing structure comprising a hollow housing element 73 in generally closing relation to one end of the heat exchanger casing and a housing element 74 in generally closing relation to one end of the valve casing. An inlet duct 75 leads to the housing element 73 and supplies to the valve and heat exchanger assembly the fluid for flow through the tubes 19. Transversely disposed in the housing element 73 is a wall 76 anchored at its one end in the rib 24 to separate the interior of the housing element 73 into upper and lower portions in accordance with the dual pass principle before described. Thus, fluid admitted from the duct 75rto the housing element 73 is restricted initially to the space above the transverse wall 76 and passes through communicating tubes 19 to the turn around chamber 26 and then returns through the lower set of tubes 19 to the space in the housing ele ment beneath wall 76. Within the wall 76 is mounted a check valve assembly comprising a housing 77 and a valve 78, the construction and arrangement being such that in the event of a flow restriction of predetermined extent in the tubes of the heat exchanger at least some of the fluid entering housing element '73 may bypass the heat exchange tubes and flow directly to the lower portion of the housing element.

Such lower portion of housing element 73 is formed with a circular projecting portion 79 registering with a similar portion 81 on the lower housing element 74. A ring 82 receives the respective portions 79 and 81 and interconnects the upper and lower housing elements. The fluid completing its passage through the heat exchanger core and returning torthe lower part of housing element a} V 73 accordingly is free to flow through the ring 82 to the lower housing element 74 where it may enter the open adjacent end of valve casing 11. Here the fluid passes through the chamber and leaves the valve casing by Way of opening 66, passing, as it does so, in contact with the thermostat 61. The latter accordingly senses the temperature of the fluid and makes corresponding and automatic adjustments in the position of the plunger 63 and thereby in the position .of the valve unit 44. In the illustrated instance, the fluid entering duct is a low temperature liquid fuel whereas the fluid entering inlet 22 is a high temperature, high pressure air or gas. The

latter descends through the tube bundle or core and exits from the heat exchanger casing by way of the openings 41 and 42, flowing, in an open position of the valve unit 44, through the valve casing to the outlet 43. Flow of the fuel is, as described, through the upper part of housing element '73 through an upper set of the tubes 19 into turn around chamber 26 and through a lower set of tubes 19 to the lower part of housing element '73 and thence to housing element 74, chamber 65 in the valve casing and out by Way of opening 66. It will be understood that in response to changing temperatures of the fuel, as sensed in chamber 65 and indicating a greater or lesser need for the addition of heat, adjustments are made in the position of the valve unit 44 to permit a greater or lesser amount of the heated air to flow through the tube bundle. Infinite variations may in this manner be made in the rate of warming of the fuel.

The valve unit 44 presents the outer surfaces of the valve portions 46 and 47 to the highvpressure high temperature air and thus tends to balance in a set position of adjustment without requiring the applicationof excessive force by the thermostat for this purpose.

What is claimed is:

1. A thermostatic valve, including a casing having a first set of openings for flow of a first fluid therethrough and a second set of openings for flow of a second fluid therethrough, said second set of openings comprising a longitudinally spaced apart pair of openings and another opening intermediate said pair of openings, means defining circular spaced apart valve seats in said casing on opposite sides of said other opening, valves to engage said seats and close off flow between said pair of openings and said other opening, means interconnecting said valves in unitary relation and comprising with said valves a valve assembly balanced by the pressure of said second fluid upon opposite faces of said valves, motion of said valve assembly in one direction being limited by said valve seats, a spring compressed by motion of said valve assembly in said one direction to urge said assembly in the opposite direction to unseat said valves, a thermostat in said casing responding to the temperature of said first fluid and extensible to move said valve assembly in said one direction, and spring means, interposed between said thermostat and said valve assembly, transmitting the extension of said thermostat to said valve assembly and absorbing over extension of said thermostat.

2. A thermostatic valve, including a casing having a first set of openings for flow of a first fluid thercthrough and a second set of openings for flow of a second fluid therethrough, said second set of openings comprising a longitudinally spaced apart pair of openings and another opening intermediate said pair of openings, means defining circular spaced apart valve seats in'said casing on opposite sides of said other openings, valves to engage said seats and close off flow between said pair of openings and said other opening, means interconnecting said valves in unitary relation and comprising with said valves a valve assembly balanced by the pressure of said second fluid upon opposite faces of said valves, motion of said valve assembly in one direction being limited by said valve seats,

a spring compressed by motion of said valve assembly in 7 said one direction to urge said assembly in the opposite direction to unseat said valve, a thermostat in said casing responding to the temperature of said first fluid and ex tensible to move said valve assembly in said one direction, spring means, interposed between said thermostat and said valve assembly, transmitting the extension of said thermostat to said valve assembly and absorbing over extension of said thermostat, a shaft mounting said valve assembly thereon and engaged by said thermostat at one end thereof for axial motion thereby in one direction in response to extension of said thermostat, said spring means being interposed between said shaft and said valve assembly to urge said shaft to axial motion in the opposite direction 10 2,864,589

and to maintain it in engagement with said thermostat, said shaft extending through and beyond said valve assembly, and sleeve means on said shaft beyond said valve assembly interposed between said assembly and said spring.

References Cited in the file of this patent UNITED STATES PATENTS 2,778,570 Carson Ian. 22, 1957 2,809,810 Carroll et al Oct. 15, 1957 Booth et a1 Dec. 16, 1958 

1. A THERMOSTATIC VALVE, INCLUDING A CASING HAVING A FIRST SET OF OPENINGS FOR FLOW OF A FIRST FLUID THERETHROUGH AND A SECOND SET OF OPENINGS FOR FLOW OF A SECOND FLUID LET, THERETHROUGH, SAID SECOND SET OF OPENINGS COMPRISING A LONGITUDINALLY SPACED APART PAIR OF OPENINGS AND ANOTHER OPENING INTERMEDIATE SAID PAIR OF OPENINGS, MEANS DEFINING CIRCULAR SPACED APART VALVE SEATS IN SAID CASING ON OPPOSITE SIDES OF SAID OTHER OPENING, VALVES TO ENGAGE SAID SEATS AND CLOSE OFF FLOW BETWEEN SAID PAIR OF OPENINGS AND SAID OTHER OPENING, MEANS INTERCONNECTING SAID VALVES IN UNITARY RELATION AND COMPRISING WITH SAID VALVES A VALVE ASSEMBLY BALANCED BY THE PRESSURE OF SAID SECOND FLUID UPON OPPOSITE FACES OF SAID VALVES, MOTION OF SAID VALVE ASSEMBLY IN ONE DIRECTION BEING LIMITED BY SAID VALVE SEATS, A SPRING COMPRESSED BY MOTION OF SAID VALVE ASSEMBLY IN SAID ONE DIRECTION TO URGE SAID ASSEMBLY IN THE OPPOSITE DIRECTION TO UNSEAT SAID VALVES, A THERMOSTAT IN SAID CASING RESPONDING TO THE TEMPERATURE OF SAID FIRST FLUID AND EXTENSIBLE TO MOVE SAID VALVE ASSEMBLY IN SAID ONE DIRECTION, AND SPRING MEANS, INTERPOSED BETWEEN SAID THERMOSTAT AND SAID VALVE ASSEMBLY, TRANSMITTING THE EXTENSION OF SAID THERMOSTAT TO SAID VALVE ASSEMBLY AND ABSORBING OVER EXTENSION OF SAID THERMOSTAT. 